Schremmer C, Lohr J E, Wastlhuber U, Kosters J, Ravelshofer K, Steinruck H, Wieler L H
Avian Pathol. 1999 Aug;28(4):349-54. doi: 10.1080/03079459994605.
A total of 103 Escherichia coli isolates from psittaciform birds were examined for the presence of genes coding for shigatoxin 1 (Stx1), shigatoxin 2 (Stx2) and for intimin (eae), using the polymerase chain reaction (PCR). Sixty-eight E. coli strains were isolated from necropsy cases and faecal samples, the other 35 were from 205 cloacal swabs from Psittaciformes with various conditions. All isolates were tested for enterohaemorrhagic E. coli-haemolysin (HlyEHEC), some also for Stx production, but there was no geno-typic or phenotypic evidence of Stx in any of them. Seven isolates, six from birds with diarrhoea, harboured the eae gene, three of them belonging to the O110:H6 serotype, one each to serotypes O153:H10, O131:H-, O63:H6 and Osp:H6. These seven eae-positive strains were negative for shigatoxin and HlyEHEC, and the hlyEHEC gene was not detectable by PCR. However, a PCR amplifying the enteropathogenic E. coli (EPEC)-specific bundle-forming pili structural gene bfpA detected four bfpA positive strains (three of serotype O110:H6, one O131:H-) among the seven eae positive strains, which classifies them as EPEC. Our findings suggest that shigatoxin-producing E. coli are uncommon, but that EPEC should be considered as potential pathogens in psittaciform birds, which may be a source of human EPEC infections.
使用聚合酶链反应（PCR）检测了从鹦鹉形目鸟类中分离出的总共103株大肠杆菌，以确定编码志贺毒素1（Stx1）、志贺毒素2（Stx2）和紧密素（eae）的基因的存在情况。68株大肠杆菌菌株是从尸检病例和粪便样本中分离出来的，另外35株来自205份患有各种病症的鹦鹉形目鸟类的泄殖腔拭子。对所有分离株进行了肠出血性大肠杆菌溶血素（HlyEHEC）检测，部分还检测了志贺毒素的产生情况，但所有分离株均未发现有基因或表型证据表明存在志贺毒素。7株分离株（6株来自腹泻鸟类）携带eae基因，其中3株属于O110:H6血清型，另外1株分别属于O153:H10、O131:H-、O63:H6和Osp:H6血清型。这7株eae阳性菌株的志贺毒素和HlyEHEC检测均为阴性，且PCR未检测到hlyEHEC基因。然而，扩增肠致病性大肠杆菌（EPEC）特异性束状菌毛结构基因bfpA的PCR在这7株eae阳性菌株中检测到4株bfpA阳性菌株（3株为O110:H6血清型，1株为O131:H-血清型），这将它们归类为EPEC。我们的研究结果表明，产志贺毒素大肠杆菌并不常见，但EPEC应被视为鹦鹉形目鸟类中的潜在病原体，可能是人类EPEC感染的来源。
